When connecting from Spira or Krono installed on a separate application server to a remote SQL server, you may have difficulties connecting. This article describes the steps for making sure that your SQL Server can be accessed remotely.
We had a customer that was using a VPN / Firewall to access our cloud instances of Spira. Most firewalls simply pass through the HTTPS traffic on port 443 unaltered. However some more stringent ones actually decrypt the HTTPS traffic, inspect the packets and then re-encrypt it for the user. In one case, this was causing an ERR_CONNECTION_CLOSED error.